Tiled displays with black-matrix support screens

ABSTRACT

A tiled display structure comprises a screen support having a screen emitter side and an opposing screen back side. A black matrix comprises a patterned layer of black-matrix material disposed on the screen back side, the pattern defining pixel openings that are substantially devoid of black-matrix material. An array of tiles comprises tiles each having a tile substrate and a plurality of pixels disposed in or on the tile substrate. Each pixel comprises one or more light emitters. The one or more light emitters are each disposed to emit light through a pixel opening in the black matrix. A substantially transparent adhesive layer adheres the array of tiles to the black-matrix material.

PRIORITY APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication No. 62/817,478, filed on Mar. 12, 2019, entitled TiledDisplays with Black-Matrix Support Screens, the content of which ishereby incorporated by reference herein in its entirety.

CROSS REFERENCE TO RELATED APPLICATIONS

Reference is made to commonly owned U.S. Pat. No. 9,741,785, filed Aug.10, 2015, entitled Display Tile Structure and Tiled Display by Bower etal., and to commonly owned U.S. Pat. No. 10,181,507, filed Jul. 17,2017, entitled Display Tile Structure and Tiled Display by Bower et al,the disclosures of each of which are incorporated herein by reference intheir entirety.

TECHNICAL FIELD

The present disclosure relates to tiled displays and in particular totiled displays that include black-matrix structures.

BACKGROUND

Large-format outdoor displays typically use inorganic light-emittingdiodes (LEDs) individually mounted in a frame and replaced as necessary.In some displays, groups of LEDs are mounted in tiles, the tiles areassembled into a tile frame, and the tile frames are mounted in adisplay frame. If an LED in a tile fails, the faulty tile is removed,and a good tile replaces the faulty tile. Tiles can be tested beforeassembly, increasing display yields. The use of tiles increases theavailable size of a display since each tile is separately made and ismuch smaller than the size of the display itself. However, the mountingdisplay frame can be larger or heavier than desired and can be visibleor create undesirable and visible seams.

A variety of tiled display structures are known. U.S. Pat. No. 5,563,470discloses a tiled panel display assembly with a common substrate onwhich multiple small display tiles are mounted in an array andelectrically interconnected to form a large-area panel display. Eachtile includes a plurality of contact pads that are aligned withcorresponding contact pads on the common substrate and are electricallyinterconnected to provide electrical connections between adjacent tiles.Each of the tiles contains a plurality of metal-filled vias that connectcontact pads on the under surfaces of the tiles to electrodes on theupper surface of the tile. Alternatively, electrical connections extendaround the outer peripheral surface of the tile substrate. U.S. Pat. No.8,531,642 shows a similar wrap-around electrical connection.

EP1548571 describes a configurable and scalable tiled OLED display. TheOLED materials are deposited in a passive-matrix configuration on atransparent substrate and then interconnected with solder bumptechnology to a printed circuit board located on top of the transparentsubstrate. U.S. Pat. No. 6,897,855 describes a different tiled OLEDstructure with display tiles having picture element (pixel) positionsdefined up to the edge of the tiles. U.S. Pat. No. 6,897,855 alsodescribes a tiled structure that employs vias through substrates toprovide the electrical connections from the driving circuitry to thepixels on the display tiles, as does U.S. Pat. No. 6,853,411. U.S. Pat.No. 6,853,411 also describes locating pixel-driving circuitry beneath anOLED light emitter. Such a structure requires additional layers in atile structure. In an alternative arrangement, U.S. Pat. No. 7,394,194describes a tiled OLED structure with electrical standoffs connectingOLED electrodes on a tile substrate with conductors on a back panel. Theelectrical standoffs are located on the edge of each tile to avoidcompromising the environmental integrity of the OLED materials on thetile.

Inorganic light-emitting diode displays using micro-LEDs (for examplehaving an area less than 100 microns square or having an area smallenough that it is not visible to an unaided observer of the display at adesigned viewing distance) are also known. U.S. Pat. No. 8,722,458,entitled Optical Systems Fabricated by Printing-Based Assembly, teachestransferring light-emitting, light-sensing, or light-collectingsemiconductor elements from a wafer substrate to a destinationsubstrate. U.S. Pat. No. 5,739,800 describes an LED display chip with anarray of micro-LEDs mounted on a mounting substrate and electricallyconnected to a driver substrate. However, this arrangement requiresmultiple substrates and the use of vias to connect integrated circuitson the driver substrate to the LED display substrate and is not suitablefor a scalable tiled structure.

Some displays use light-emitting structures on a backplane together withintegrated circuits mounted on the backplane to provide control signalsto the light-emitting structures. As discussed in U.S. Pat. No.5,686,790, integrated circuits mounted on the light-emitting side of thebackplane unnecessarily increase the size of the backplane whileintegrated circuits mounted on the side of the backplane opposite thelight-emitting structures require electrical vias through the backplaneor electrical leads wrapped around the edge of the backplane toelectrically connect the integrated circuits with the light-emittingstructures. Such vias and leads are difficult and expensive toconstruct. Integrated circuits located within the display area of adisplay reduce the resolution and aperture ratio of the display. Inflat-panel displays such as LCDs and OLEDs, a reduced aperture ratioalso reduces the brightness or lifetime of the display.

Light-absorbing black-matrix layers are commonly used to absorb ambientlight in a display and are typically disposed in a layer coated over alight-emitter layer in the display. Such black-matrix layers improve thecontrast of the display. U.S. Pat. No. 7,239,367 entitled Tiled DisplayDevice with Black Matrix Film having Different Aperture Ratios to Jin etal., describes such a display.

Multi-layer printed circuit boards (PCBs) are widely used in digitalelectronic systems to interconnect electronic elements such asintegrated circuits and passive components such as resistors andcapacitors. Such printed circuit boards include layers of insulatingmaterial interdigitated with patterned conductive layers such as etchedcopper sheets laminated with electrically conductive through-hole viasto interconnect the electronic elements, for example as disclosed inU.S. Pat. No. 4,591,659. However, these PCBs can be limited in thespatial resolution provided for integrated circuit electricalinterconnections. Daughter cards used in conjunction with motherboards(i.e., smaller printed circuit boards mounted upon and electricallyconnected to larger printed circuit boards) are also known but likewisehave limited spatial resolution, orientation, and integration providedfor integrated circuits.

Thus, there remains a need for a display tile structure that is simpleto make and has increased contrast, manufacturability, and an improvedform factor in a robust structure for a tiled display.

SUMMARY

In some embodiments of the present disclosure, a tiled display structurecomprises a screen support having a screen emitter side and an opposingscreen back side. The tiled display structure can have only a singlescreen support. A black matrix comprises a patterned layer ofblack-matrix material disposed on the screen back side. The patterndefines pixel openings substantially devoid of black-matrix material. Anarray of tiles each comprise a tile substrate and a plurality of pixelsdisposed in or on the tile substrate. Each pixel comprises one or morelight emitters. The one or more light emitters are each disposed to emitlight through a pixel opening in the black matrix. A substantiallytransparent adhesive layer adheres the array of tiles to theblack-matrix material.

In some embodiments, each of the pixels can comprise a plurality oflight emitters and the plurality of light emitters of each pixel emitlight through a common pixel opening in the black matrix. In someembodiments, each pixel comprises a plurality of light emitters and eachlight emitter of the plurality of light emitters of each pixel emitslight through a different pixel opening in the black matrix.

In some embodiments, each of the pixels comprises a red-light emitterthat emits red light, a green-light emitter that emits green light, anda blue-light emitter that emits blue light. One or more light emittersof each pixel of the plurality of pixels can each be a light-emittingdiode (LED). Each of the light-emitting diodes can be a micro-LED havingat least one of a length and width no greater than 200 microns, nogreater than 100 microns, no greater than 50 microns, no greater than 20microns, no greater than 10 microns, no greater than 5 microns, or nogreater than 2 microns. Each light-emitting diode can comprise afractured or separated tether.

In some embodiments, at least some of the pixel openings comprise acolor filter. In some embodiments, black-matrix material is disposed incontact with and disposed between tile substrates and can adhere tilesubstrates together.

In some embodiments, two or more adjacent tiles in the array of tilesare butted together. In some embodiments, the pixels are disposed at aregular pixel pitch in a direction and the pixel openings have anopening size in the direction that is no greater than one half the pixelpitch, no greater than one quarter the pixel pitch, no greater than onefifth the pixel pitch, no greater than one tenth the pixel pitch, nogreater than one twentieth the pixel pitch, no greater than one fiftieththe pixel pitch, no greater than one hundredth the pixel pitch, nogreater than one five hundredth the pixel pitch, or no greater than onethousandth the pixel pitch. In some embodiments, the pixels are disposedat a regular pixel pitch in a direction and a distance between a pixelat an edge of a tile and the edge of the tile is no greater than onehalf the pixel pitch.

The substantially transparent adhesive can be an optically clearadhesive. An optically clear adhesive can have a transparency of, forexample, no less than 50% (e.g., no less than 75%, no less than 85%, noless than 90%, no less than 95%, or no less than 98%) to light, forexample visible light or light emitted by the one or more lightemitters.

Each tile substrate of the array of tiles can have a tile emitter sideand a tile back side and the one or more light emitters disposed on thetile substrate are disposed on the tile emitter side. Emitter-sideelectrodes can be disposed on the tile emitter side and back-sideelectrodes can be disposed on the tile back side and electricalconnections can electrically connect the emitter-side electrodes to theback-side electrodes. The electrical connections can be made withthrough-via connections that pass through the tile substrate or can bemade with wrap-around connections that are at least partly disposed onone or more edges of the tile substrate.

In some embodiments, each tile comprises a pixel controller disposed onthe tile back side electrically connected to the back-side electrodesthat controls the one or more light emitters in each of the pixelsdisposed on the tile substrate.

Tiled display structures can comprise one or more bus connections andthe one or more bus connections can be electrically connected to theback-side electrodes of at least one tile. Each tile can comprise one ormore separate bus connections electrically connected to the back-sideelectrodes of the tile. The back-side electrodes of one tile can beelectrically connected to the back-side electrodes of an adjacent tileadjacent to the one tile. The back-side electrodes of one tile can beelectrically connected to the back-side electrodes of an adjacent tileadjacent to the one tile with one or more of: a jumper comprising ajumper substrate, connection posts, and a fractured or separated tether,one or more wire bonds, and one or more wrapped connections.

In some embodiments, at least some of the back-side electrodes of asubset of the array of tiles are commonly connected and each of thecommonly connected back-side electrodes is electrically connected to abus connection. In some embodiments, the tiles are disposed in rows andthe back-side electrodes of ones of the tiles in a row are electricallyconnected in common.

In some embodiments, the tile substrates are flexible substrates. Insome embodiments, a portion of one tile substrate is at least partiallyfolded behind a portion of another tile substrate adjacent to the onetile substrate, as viewed through the screen support. The portion of theone tile substrate can be a bezel portion or a pigtail portion. In someembodiments, the tile substrates comprise a pigtail that electricallyconnects the one or more light emitters to a bus connection.

The use of small, bright emitters, for example micro-LEDs, enables alow-aperture ratio display, in contrast to OLED displays and LCDs,having increased area for interconnections between the light emitters aswell as additional circuitry that enhances the functionality of thetiles. A low-aperture ratio display (for example having an apertureratio of no greater than 20%, no greater than 10%, no greater than 1%,no greater than 0.5%, or no greater than 0.1%) can enable visuallyseamless tiling by increasing the distance between a pixel and an edgeof a tile substrate.

Furthermore, the present disclosure enables reduced-cost construction byproviding tiles that are formed using very small components, for examplemicro-LEDs disposed on the tiles by micro-transfer printing, and smallinterconnections, for example made using photolithographic methods thatenable a very high-resolution display that is then electricallyconnected to low-resolution contact pads electrically available to busconnectors, which can then be constructed using a much lower resolutionand less expensive technology, for example using parts, materials, andmethods that are commonly used in printed circuit board manufacturing. Apixel controller can control more than one pixel, for example all of thepixels on a tile substrate.

Tiles can also be made on a flexible tile substrate disposed on a rigidtile substrate that is subsequently removed, thereby forming a very thinstructure that can be flexible. If the screen support is also flexible,very large, flexible displays can be constructed.

In certain embodiments, the display includes a plurality of tiles withlight emitters arranged in a regular array. In certain embodiments, thedisplay includes an index matching or light-absorbing layer locatedbetween the tiles. In certain embodiments, the tile comprises glass, apolymer, a curable polymer, sapphire, silicon carbide, metal, copper, ordiamond.

In certain embodiments, the tile comprises one or more passiveelectrical components mounted onto, formed on, or formed in a tilesubstrate. In certain embodiments, the passive electrical components areresistors, capacitors, antennas, or inductors. In certain embodiments,the tile includes one or more active electrical components mounted onto,formed on, or formed in a tile substrate. In certain embodiments, theactive electrical components are transistors, integrated circuits, powersupplies, or power-conversion circuits. In certain embodiments, at leastone of the active electrical components is a driver that drives one ormore of the light emitters.

In certain embodiments, the light-emitter is a red-light emitter thatemits red light, and some embodiments comprise a green-light emitterthat emits green light and a blue-light emitter that emits blue light.In certain embodiments, the tile includes a plurality of pixels andlight emitters. In certain embodiments, the tile includes redundantred-light, green-light, and blue-light emitters. In certain embodiments,the red, green, and blue light emitters form a full-color pixel in adisplay.

In some embodiments, a structure includes a tiled display including aplurality of tiles. The tiles can be display tiles and can be removableor replaceable.

In some embodiments, a method of making a tiled display structurecomprises: providing a plurality of tiles, each of the tiles comprisinga tile substrate and a plurality of pixels disposed in or on the tilesubstrate, each pixel comprising one or more light emitters; providing ascreen support having a screen emitter side and an opposing screen backside; providing a black matrix comprising a patterned layer ofblack-matrix material disposed on the screen back side, the patterndefining pixel openings that are substantially devoid of black-matrixmaterial; and adhering the tiles to the black matrix with a layer ofsubstantially transparent adhesive such that each of the one or morelight emitters of each of the plurality of tiles is disposed to emitlight through one of the pixel openings in the black matrix.

In some embodiments, providing the black matrix comprises disposing[e.g., printing (e.g., ink-jet printing) or coating] the black-matrixmaterial on the screen support in a patterned layer. In someembodiments, providing the black matrix comprises photolithographicallyprocessing an unpatterned layer of black-matrix material [e.g., formedby printing or coating (e.g., spin-coating)] to form the patterned layerof the black-matrix material.

In some embodiments, disposing the layer of substantially transparentadhesive on the black matrix (e.g., and in the pixel openings) and thenadhering the tiles to the layer of substantially transparent adhesive.In some embodiments, the method comprises arranging the tiles in anarray; disposing the layer of substantially transparent adhesive on thetiles; and adhering the black matrix to the layer of substantiallytransparent adhesive. In some embodiments, the method comprises:determining that each of one or more of the tiles is a defective (e.g.,by visual inspection or optical, electronic, or optoelectronic testing);removing (e.g., peeling off) the one or more of the tiles that isdefective from the layer of substantially transparent adhesive; andadhering an additional tile to the layer of substantially transparentadhesive for each of the one or more of the tiles that was removed. Insome embodiments, the method comprises: determining whether theadditional tile that replaced the one or more of the tiles that wasdefective is defective; and replacing any additional tile that isdetermined to be defective.

The present disclosure provides, inter alia, a tiled display havingreduced thickness, improved functionality and manufacturability, andreduced manufacturing cost, as well as improved contrast and uniformity.In some embodiments, a single screen support can provide a globalreference for all of the tile substrates of tiles, which reducesalignment runout and improve uniformity.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, aspects, features, and advantages ofthe present disclosure will become more apparent and better understoodby referring to the following description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a cross section with an inset top view of a pixel on a tilesubstrate according to some illustrative embodiments of the presentdisclosure;

FIGS. 2-4 are cross sections of tiles according to some illustrativeembodiments of the present disclosure;

FIGS. 5-6 are cross sections of adjacent tiles according to someillustrative embodiments of the present disclosure;

FIGS. 7-8 are cross sections of tiles according to some illustrativeembodiments of the present disclosure;

FIGS. 9-11 are cross sections of electrically connected adjacent tilesaccording to some illustrative embodiments of the present disclosure;

FIGS. 12-13 are bottom views of electrically connected adjacent tilesaccording to some illustrative embodiments of the present disclosure;

FIGS. 14-15 are bottom views of a one-dimensional and two-dimensionalarray of tiles, respectively, according to some illustrative embodimentsof the present disclosure;

FIGS. 16-17 are bottom views of tiles according to some illustrativeembodiments of the present disclosure;

FIG. 18 is a top view through the screen support according to someillustrative embodiments of the present disclosure;

FIG. 19 is a cross section of a tile according to some illustrativeembodiments of the present disclosure;

FIG. 20A shows an example of a tiled display structure that includes a2-D display tile array, according to some illustrative embodiments ofthe present disclosure;

FIG. 20B shows an example of a tiled display structure that includes a1-D display tile array, according to some illustrative embodiments ofthe present disclosure;

FIG. 21A shows an example of a tiled display structure that includes a2-D display tile array, according to some illustrative embodiments ofthe present disclosure;

FIG. 21B shows an example of a tiled display structure that includes a1-D display tile array, according to some illustrative embodiments ofthe present disclosure;

FIG. 22 shows a view of a tiled display structure that includes adisplay tile array, according to some illustrative embodiments of thepresent disclosure;

FIG. 23 shows display tiles being prepared in an array for mounting to ahost screen panel, according to some illustrative embodiments of thepresent disclosure; and

FIG. 24 shows front-to-back (e.g., wrap-around) electrical connectionsfor electrically connecting a display tile, according to someillustrative embodiments of the present disclosure.

Features and advantages of the present disclosure will become moreapparent from the detailed description set forth below when taken inconjunction with the drawings, in which like reference charactersidentify corresponding elements throughout. In the drawings, likereference numbers generally indicate identical, functionally similar,and/or structurally similar elements. The figures are not necessarilydrawn to scale since the variation in size of various elements in theFigures is generally too great to permit depiction to scale.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS

Referring to the cross section and inset of FIG. 1, a tiled displaystructure 99 comprises a screen support 10 having a screen emitter side12 and an opposing screen back side 14. Screen support 10 can be asingle screen support and can serve as a display substrate for the tileddisplay structure 99. A black matrix 20 comprising a patterned layer ofblack-matrix material 22 is disposed on screen back side 14. Thepatterned layer defines pixel openings 24 that are substantially devoidof black-matrix material 22. An array of tiles 40 each comprises a tilesubstrate 42 having a tile emitter side 44 and an opposing tile backside 46 and a plurality of pixels 50 disposed in or on tile substrate42, for example on tile back side 46. Each pixel 50 comprises one ormore light emitters 52. The one or more light emitters are 52 are eachdisposed to emit light 90 through a corresponding pixel opening 24. Asubstantially transparent adhesive layer 30 of substantially transparentadhesive adheres the array of tiles 40 to black-matrix material 22.Transparent adhesive layer 30 can be a releasable adhesive so that tiles40 can be removed (e.g., by peeling) and replaced. Pixels 50 cancomprise a plurality of light emitters 52 and can be controlled by pixelcontroller 56 electrically connected to pixels 50 by emitter-sideelectrodes 60, for example in an active-matrix embodiment. Pixelcontroller 56 can control all of pixels 50 in a tile 40 or multiplepixel controllers 56 can be provided, for example for some but not allof pixels 50 in a tile 40 or for individual pixels 50 or for individualsubpixels of pixels 50.

Screen support 10 can comprise any useful substrate, for example asfound in the display industry, capable of transmitting light 90 emittedby light-emitters 52, for example but not limited to glass, plastic,sapphire, or quartz. Screen emitter side 12 and opposing screen backside 14 can be substantially or effectively parallel, for example withinthe limitations of a suitable manufacturing process. Screen support 10can comprise one or more fiducial markings, for example one or morescreen fiducial markings for aligning screen support 10 and tilefiducial markings to facilitate alignment of tiles 40 with screensupport 10. Screen support 10 can be substantially transparent to light90 emitted from light emitters 52, for example at least 50% (e.g., atleast 75%, at least 80%, at least 90%, at least 95%, or at least 98%)transparent to visible light.

Black-matrix material 22 can comprise a polymer or resin and can becurable so that it can be applied as a liquid (e.g., a viscous liquid)to screen back side 14 and cured to form a solid. Black-matrix material22 can comprise carbon black, dyes, pigments, or other visiblelight-absorbing material, for example having a black appearance to ahuman observer. Black-matrix material 22 can be patterned usingphotolithographic processes known in the display art, such as spray orspin coating and patterning with photoresist, to form black matrix 20defining pixel openings 24. Pixel openings 24 can be substantiallytransparent to light 90 emitted from light emitters 52, for example atleast 50% (e.g., at least 75%, at least 80%, at least 90%, at least 95%,or at least 98%) transparent to visible light.

Adhesive layer 30 can comprise a curable material, for example a resinor polymer that can be cured with heat or radiation, for exampleultra-violet radiation. Adhesive layer 30 can be a layer of opticallyclear adhesive. In some embodiments, adhesive layer 30 is a layer ofcommercially available optically clear adhesive (e.g., provided asliquid optically clear adhesive (LOCA) and then cured). Adhesive layer30 can be non-curable or comprise a cured material, such as PDMS forexample. Adhesive layer 30 can provide an adhesion from which tiles 40can be removed or replaced, for example by peeling a defective tile 40from adhesive layer 30 and then pressing a new tile 40 onto adhesivelayer 30. For example, if a tile 40 fails, the failed tile 409 can beremoved and another tile 40 adhered in its place. PDMS can provide suchan adhesive layer 30 that allows for removal and replacement ofdefective tiles 40. Adhesive layer 30 can be substantially transparentto light 90 emitted from light emitters 52, for example at least 50%(e.g., at least 75%, at least 80%, at least 90%, at least 95%, or atleast 98%) transparent to visible light.

Tile substrate 42 can be rigid or flexible and can, for example,comprise glass, or polymer, or other materials known in the display orintegrated circuit industry. Tile substrate 42 can be, but need notnecessarily be, transparent. In some embodiments of the presentdisclosure, tile substrate 42 is opaque or is partially coated with alight-absorbing layer, for example a polymer layer comprising carbonblack, dyes, or pigments. In some embodiments, tile substrate 42 can beprocessed using photolithographic processes known in the display arts.The array of tiles 40 can be arranged in a rectangular array or in a rowor column. Tile emitter side 44 and opposing tile back side 46 can besubstantially or effectively parallel, for example within thelimitations of a suitable manufacturing process. Tile substrate 42 cancomprise one or more fiducial markings to facilitate alignment of tiles40 with screen support 10.

Light emitters 52 can comprise inorganic light-emitting diodes (iLEDs)and can be disposed on tile emitter side 44 of tile substrate 42 bymicro-transfer printing the iLEDs from a native LED source wafer to tileemitter side 44 of non-native tile substrate 42. As a part of themicro-transfer printing process, micro-LED light emitters 52 cancomprise a fractured or separated light-emitter tether 54 (for exampleas shown in FIG. 4). Micro-transfer printed inorganic micro-LEDs can berelatively small, for example having at least one of a width and alength no greater than 200 microns (e.g., no greater than 100 microns,no greater than 50 microns, no greater than 20 microns, no greater than10 microns, no greater than 5 microns, or no greater than 2 microns).Light emitters 52 can be interconnected on tile emitter side 44 withemitter-side electrodes 60, for example using photolithographicprocesses and materials to construct patterned electrical wires on tilesubstrate 42 and light emitters 52, as discussed further below.

Referring to FIGS. 2 and 3, pixels 50 comprise three light emitters 52,a red-light emitter 52R that emits red light, a green-light emitter 52Gthat emits green light, and a blue-light emitter 52B that emits bluelight. Referring to FIG. 2, the plurality of light emitters 52R, 52G,52B of each pixel 50 can emit light 90 through a single, common pixelopening 24 in black matrix 20. As shown in FIG. 3, red, green, and bluelight emitters 52R, 52G, 52B of each pixel 50 can each emit light 90through a different pixel opening 24 in black matrix 20.

In some embodiments of the present disclosure, pixel openings 24 areempty (e.g., comprise air or a gas or are under vacuum). In someembodiments, pixel openings 24 comprise a transparent material (e.g.,the transparent adhesive material of adhesive layer 30). Referring toFIG. 4, at least some of pixel openings 24 comprise a color filter 26.Color filter 26 can, for example, filter light 90 emitted fromcorresponding light emitters 50. Color filter 26 can improve the qualityof the emitted light, for example improving the purity of emitted light90 to improve the color gamut of tiled display structure 99.

Referring to FIG. 5, black-matrix material 22 is disposed between and incontact with two or more adjacent tiles 40. Adjacent tiles 40 are twotiles 40 that do not have any other tile 40 between them. Black-matrixmaterial 22 can absorb light and can hide or obfuscate the seams betweenadjacent tiles 40. Black-matrix material 22 can also adhere adjacenttiles 40 together, increasing the physical robustness of tiled displaystructure 99.

Referring to FIG. 6, two or more adjacent tiles 40 are butted togetherand adhered to a single screen support 10. In some embodiments of thepresent disclosure and as illustrated in FIG. 6, pixels 50 are disposedat a regular pixel pitch P in a direction and pixel openings 24 have anopening size O in the direction that is no greater than one of halfpixel pitch P, no greater than one quarter of pixel pitch P, no greaterthan one fifth of pixel pitch P, no greater than one tenth of pixelpitch P, no greater than one twentieth of pixel pitch P, no greater thanone fiftieth of pixel pitch P, no greater than one hundredth of pixelpitch P, no greater than one five hundredth of pixel pitch P, or nogreater than one thousandth of pixel pitch P. In some embodiments,pixels 50 are disposed at a regular pixel pitch P in a direction and anedge distance E between a pixel 50 at an edge of a tile substrate 42 andthe edge of the tile substrate 42 is no greater than one half pixelpitch P.

Referring to FIGS. 7 and 8, tiles 40 comprise tile substrate 42 withtile emitter side 44 and opposing tile back side 46. One or moreemitter-side electrodes 60 are disposed on tile emitter side 44 and canbe electrically connected to light emitter 52 electrical contacts toprovide electrical signals to light emitter 52 and causing light emitter52 to emit light 90. Back-side electrodes 62 are disposed on tile backside 46 and can be electrically connected to emitter-side electrodes 60,for example with through-via connections 64 that pass through tilesubstrate 42 (as shown in FIG. 7) or with wrap-around connections 66that extend over an edge of tile substrate 42 (as shown in FIG. 8).Back-side electrodes 62 can be electrically connected to power, ground,or control signals from a tiled display structure 99 controller externalto tiled display structure 99 (not shown). Each light emitter 52 inpixel 50 can be similarly connected (e.g., with its own emitter-sideelectrode 60 and back-side electrode 62 or with a common emitter-sideelectrode 60 or back-side electrode 62).

Adjacent tiles 40 can be electrically connected together, for example asshown in FIGS. 9-11. Referring to FIG. 9, a jumper 70 comprising ajumper substrate 72 with jumper connection posts 74 extending away fromjumper substrate 72, for example spikes having a sharp point,electrically connects back-side electrodes 62 on adjacent tilesubstrates 42. In some embodiments, jumper 70 can be micro-transferprinted from a native jumper source wafer to non-native tile substrate42 can comprise a fractured or separated jumper tether 76. Referring toFIG. 10, back-side electrodes 62 on adjacent tile substrates 42 areelectrically connected by wrap-around connections 66 butted together.Referring to FIG. 11 (and in some embodiments FIG. 25), back-sideelectrodes 62 on adjacent tile substrates 42 are electrically connectedby bond wires 68 (also known as wire bonds) and wrap-around connections66 are insulated with insulator 67 to prevent undesired electricalconnections. Adjacent tiles 40 can be electrically connected in a row ortwo-dimensional array of tiles 40, for example a sub-array of the arrayof tiles 40, for example as shown in the FIG. 12 row of tiles 40.

In some embodiments of the present disclosure, and as shown in FIG. 12,groups (e.g., sub-arrays) of tiles 40 in the array of tiles 40 areelectrically connected together and each group is electrically connectedto a separate bus connection 80, for example a group of electricalconnections in a common cable with multiple wires are electricallyconnected to back-side electrodes 62 so that the group of tiles 40 iscontrolled by an external tiled display structure 99 controller. Thegroup of tiles 40 can be arranged in one dimension (e.g., a row of tiles40, as in FIG. 12) or in two dimensions, for example in a two-by-twoarray (e.g., as shown in FIG. 13).

In some embodiments of the present disclosure and as shown in theone-dimensional tile array of FIG. 14 and the two-dimensional tile arrayof FIG. 15 (e.g., and as also shown in FIGS. 21A, 21B, and 22), eachtile 40 in the array of tiles 40 is separately connected to a separatebus connection 80, for example a group of electrical connections in acommon cable with multiple wires are electrically connected to back-sideelectrodes 62 so that each tile 40 is independently controlled by anexternal tiled display structure 99 controller. (For clarity, only someof the separate bus connections are illustrated in FIGS. 14 and 15, but,according to some embodiments, a bus connection 80 is electricallyconnected to several or every tile 40 in the array of tiles 40.)Referring to FIG. 16 (and in some embodiments, FIG. 24), each tilesubstrate 42 can comprise a pigtail 48 that extends from a portion oftile substrate 42 on which the one or more light emitters 52 aredisposed and provides access to back-side electrodes 62 to enableelectrical connections to bus connections 80, for example with aconnector. Referring to FIG. 17, each tile substrate 42 can comprise abezel 82 surrounding the one or more light emitters 52 that can befolded to enable a closer arrangement of adjacent tiles 40. A bezelportion 82 is a perimeter portion of a display or display tile substrate42 that is exterior to a display area in which light emitters 52 aredisposed, e.g., as shown in FIG. 17. FIG. 21C describes various featuresthat can be, but are not necessarily, included in a one-dimensional ortwo-dimensional array of tiles 40 in a tiled display structure 99.

FIG. 18 illustrates a top view of tiled display structure 99 accordingto some embodiments viewed through screen support 10 through whichpixels 50 emit light. Referring to FIG. 18, tile substrates 42 can beflexible so that a portion of one tile substrate 42 is at leastpartially folded behind (e.g., when viewed from screen support 10 side)a portion of another tile substrate 42 adjacent to the one tilesubstrate 42. For example, a bezel portion 82 or a pigtail portion 48(e.g., as in FIGS. 17, 16) can be at least partially folded behind anadjacent tile substrate 42 on a side of tile substrate 42 oppositescreen support 10, thereby mechanically enabling a bezel-free multi-tiledisplay area or enabling electrical connections to each tile 40 from anexternal tiled display structure 99 controller.

FIGS. 19 and 23A illustrate a portion of tile 40 in more detail,according to some embodiments. FIGS. 19 and 23A illustrate tilesubstrate 42, emitter-side electrodes 60 electrically contacting lightemitter 52 through light-emitter connection posts 58 and back-sideelectrode 62 with wrap-around connection 66 insulated by insulator 67.Bus connection 80 can contact back-side electrode 62 with an electricalconnection that can be facilitated with, for example, a solder joint ora connector. FIG. 23B describes various features that can be, but arenot necessarily, included in a tiled display structure 99.

Tiled display structure 99 can be constructed by providing a screensupport 10 and tile substrates 42. Black-matrix material 22 is coated onscreen support 10 and patterned to define pixel openings 24 inblack-matrix material 22, for example using pattern-wise exposedcoatings of photo-resist that are developed, etched, and stripped, usingconventional photolithographic methods. One or more fiducials can bedefined on screen support 10. Tile substrates 42 are provided andback-side electrodes 62 and emitter-side electrodes 60 provided on tileemitter side 44 and tile back side 46, respectively, together witheither through-via connections 64 or wrap-around connections 66. Lightemitters 52 can be disposed on tile emitter side 44, for example bymicro-transfer printing so that light-emitter tethers 54 are fracturedor separated and light-emitter connection posts 58 pierce or otherwisecontact emitter-side electrodes 60. Light emitters 52 emit light 90 in adirection opposite to tile substrate 42 into pixel openings 24 andthrough screen support 10. Screen support 10 can comprise additionallayers, for example anti-reflection layers. Adhesive layer 30 isdisposed on either black matrix 20 or tiles 40, tiles 40 are thenaligned with screen support 10 and adhered together. If adhesive layer30 is curable, adhesive layer 30 is then cured. In some embodiments,adhesive layer 30 is a pressure-sensitive adhesive and tiles 40 arepressed onto adhesive layer 30. In some embodiments, a tile 40 isdiscovered to be defective (e.g., by visual inspection or optical,electronic, or optoelectronic testing), is removed by peeling thedefective tile 40, and replacing the defective tile 40 with another tile40, by pressing the other tile 40 into the location of the removeddefective tile 40.

In some embodiments, in operation, a display controller external totiled display structure 99 provides control and power signals to tiles40 in the array of tiles 40 for example through bus connections 80. Busconnections 80 can be provided individually to each tile 40 or providedto groups or subsets of tiles 40 having interconnected back-sideelectrodes 62. In some embodiments, the group of tiles 40 comprises allof tiles 40. Back-side electrodes 62 conduct the provided power andcontrol signals to each pixel controller 56 (where present), pixels 50,and light emitters 52 to operate light emitters 52. Thus, tiled displaystructure 99 can provide an active-matrix display, or a passive-matrixdisplay, such as in inorganic micro-light-emitting diode display.

Certain embodiments of the present disclosure provide a tiled displaystructure for large displays (e.g., in excess of 3 m² in display area).Certain embodiments provide one or more of: a large display from smallerpieces (tiles), invisible (e.g., to an unaided human viewer) seamsbetween tiles of a display, very low reflectance, high ambient contrast,customizable “off state” appearance of a display, tiled active orpassive matrix displays, displays with replaceable tiles. In certainembodiments, a display includes a host screen panel (e.g., screensupport 10) with an opaque film that has windows with a pitch equal to apixel pitch and window size smaller than half of the pixel pitch (e.g.,smaller than 20% of the pixel pitch). The display may include emissivepixels having a core area in which multiple colored emitters of thepixel are located, where the core area is smaller than the windows inthe opaque film. In some embodiments, a rectangular emissive displaytile includes pixels having core areas in which multiple emitters arearranged, where the pixels are arranged in columns and rows and at leastone edge of the tile is located a distance from the core areas of thenearest row or column of pixels by less than one half of a pixel pitch.In some embodiments, an optically clear adhesive layer connects a hostscreen panel to a display tile (e.g., a rectangular display tile). Forexample, a polydimethylsiloxane (PDMS) elastomer film can be applied toa host screen panel and cured.

FIG. 20A shows an example of a 2-D display tile array (each including acontrol chip (e.g., pixel controller 56)) on a host screen panel (e.g.,screen support 10). FIG. 20B shows an example of a 1-D display tilearray on a host screen panel. FIG. 21A shows an additional example of a2-D tile array and FIG. 21B shows an additional example of a 1-D tilearray. An array of display tiles can be a bezel free display. Displaytiles can include and/or be electrically connected with front-to-backelectrical connections (e.g., wrap-around plated metal,through-substrate vias, through-substrate leads, or a wrap-aroundflexible connector). A display panel can be flexible. Host screen panelsize can be, for example, in a range of 1 to 10 m×0.2 to 4 m (e.g.,having a rectangular shape). A host screen panel can include or be madefrom, for example, glass, film, or web. Tile size can be, for example,between 2 inches and 60 inches on a diagonal. A display tile can includeor be made from, for example, glass, ceramic, or an organic. Moldingcompound, polyimide, or the like can be included in a display tile orused to mount a display tile. A bond surface of a display tile can befluorinated.

FIG. 22 shows an example of a tiled display structure 99 that includeshost screen (e.g., screen support 10) and different display tiles 40with different styles of front-to-back electrical connections (wraparound or through substrate via (e.g., through substrate pillar)) on thehost screen. Table 1 describes example specifications of characteristicsthat can be used in forming a tiled display structure 99 as shown inFIG. 22 (or other tiled display structures 99 disclosed herein). FIG. 23shows flexible display tiles forming front-to-back electricalconnections that can be mounted in an array on a host screen panel(e.g., support screen 10). FIG. 24 shows a display tile that includes acontrol chip (e.g., pixel controller 56) and a front-to-back electricalconnection that is a wrap-around connection (can be used with or withoutan insulator to electrically isolate the connection). Examples offront-to-back electrical connections include flex circuit (e.g., withcopper traces) and weldable wires that connect top surface to bottomsurface. Front-to-back electrical connections can be used with a displaytile 40 in accordance with FIG. 19, for example.

TABLE 1 within about micro-LEDs and 0.1 mm diameter controller Can belocated on the surface of the display tile closest to the host screenFront-to-back Can be, for Wrap around can connection example, wrap-benefit from “electrical around or through- insulator spacer” tosubstrate via avoid unintentional (e.g., pillar) electrical connectionto neighboring display tiles Wrap around plated or printed conductor canbe patterned by laser cutting, for example Adhesive Can be opticallyPDMS elastomer can clear, optionally provide reversible with reversibleadhesion to many adhesion and cured surfaces, e.g. surfaces beforejoining functionalized with display tiles to fluorine compounds, hostscreen for reversible removal of display tiles and re-application ofdisplay tiles Adhesive Optionally about Optionally, thin bond thickness0.01 to 0.05 mm line to maximize transmission of light through windowsin the host screen

As is understood by those skilled in the art, the terms “over” and“under” are relative terms and can be interchanged in reference todifferent orientations of the layers, elements, and substrates includedin the present disclosure. For example, a first layer on a second layer,in some implementations means a first layer directly on and in contactwith a second layer. In other implementations a first layer on a secondlayer includes a first layer and a second layer with another layertherebetween.

Having described certain implementations of embodiments, it will nowbecome apparent to one of skill in the art that other implementationsincorporating the concepts of the disclosure may be used. Therefore, theinvention should not be limited to the expressly described embodiments,but rather should be limited only by the spirit and scope of thefollowing claims.

Throughout the description, where apparatus and systems are described ashaving, including, or comprising specific components, or where processesand methods are described as having, including, or comprising specificsteps, it is contemplated that, additionally, there are apparatus, andsystems of the disclosed technology that consist essentially of, orconsist of, the recited components, and that there are processes andmethods according to the disclosed technology that consist essentiallyof, or consist of, the recited processing steps. It should be understoodthat the order of steps or order for performing certain action isimmaterial so long as the disclosed technology remains operable.Moreover, two or more steps or actions in some circumstances can beconducted simultaneously.

PARTS LIST

-   E edge distance-   O opening size-   P pixel pitch-   10 screen support-   12 screen emitter side-   14 screen back side-   20 black matrix-   22 black-matrix material-   24 pixel opening-   26 color filter-   30 adhesive layer-   40 tile-   42 tile substrate-   44 tile emitter side-   46 tile back side-   48 pigtail-   50 pixel-   52 light emitter-   52R red-light emitter-   52G green-light emitter-   52B blue-light emitter-   54 light-emitter tether-   56 pixel controller-   58 light-emitter connection posts-   60 emitter-side electrode-   62 back-side electrode-   64 through-via connection-   66 wrap-around connection-   67 insulator-   68 wire bond-   70 jumper-   72 jumper substrate-   74 jumper connection post-   76 jumper tether-   80 bus connections-   82 bezel portion-   90 light-   99 tiled display structure

1. A tiled display structure, comprising: a screen support having ascreen emitter side and an opposing screen back side; a black matrixcomprising a patterned layer of black-matrix material disposed on thescreen back side, the pattern defining pixel openings that aresubstantially devoid of black-matrix material; an array of tiles, eachtile comprising a tile substrate and a plurality of pixels disposed inor on the tile substrate, each pixel comprising one or more lightemitters, wherein the one or more light emitters are each disposed toemit light through a pixel opening in the black matrix; and asubstantially transparent adhesive layer adhering the tiles to theblack-matrix. 2-4. (canceled)
 5. The tiled display structure of claim 1,wherein each of the one or more light emitters of each pixel of theplurality of pixels is a light-emitting diode (LED) and thelight-emitting diode comprises a fractured or separated tether. 6-9.(canceled)
 10. The tiled display structure of claim 1, wherein two ormore adjacent tiles in the array of tiles are butted together.
 11. Thetiled display structure of claim 1, wherein the pixels are disposed at aregular pixel pitch in a direction and wherein the pixel openings havean opening size in the direction that is no greater than one half thepixel pitch.
 12. The tiled display structure of claim 1, wherein thepixels are disposed at a regular pixel pitch in a direction and whereina distance between a pixel at an edge of a tile and the edge of the tileis no greater than one half the pixel pitch.
 13. (canceled)
 14. Thetiled display structure of claim 1, wherein, for each tile of the arrayof tiles, the tile substrate of the array of tiles has a tile emitterside and a tile back side and wherein the pixels disposed on the tilesubstrate are disposed on the tile emitter side.
 15. The tiled displaystructure of claim 14, comprising, for each tile of the array of tiles,(i) emitter-side electrodes disposed on the tile emitter sideelectrically connected to the pixels, and (ii) back-side electrodesdisposed on the tile back side, and (iii) electrical connectionselectrically connecting the emitter-side electrodes to the back-sideelectrodes.
 16. The tiled display structure of claim 15, wherein theelectrical connections are through-via connections that pass through thetile substrate or are wrap-around connections on an edge of the tilethat are at least partly disposed on one or more edges of the tilesubstrate.
 17. The tiled display structure of claim 15, wherein each ofthe tiles comprises a pixel controller disposed on the tile back side,the pixel controller electrically connected to the back-side electrodes,and the pixel controller controlling the one or more light emitters ineach of the pixels dispones on the tile substrate.
 18. The tiled displaystructure of claim 15, comprising one or more bus connections andwherein the one or more bus connections are electrically connected tothe back-side electrodes of at least one tile.
 19. The tiled displaystructure of claim 18, wherein each of the tiles comprises one or moreseparate bus connections electrically connected to the back-sideelectrodes of the tile.
 20. The tiled display structure of claim 15,wherein the back-side electrodes of one of the tiles are electricallyconnected to the back-side electrodes of an adjacent tile that isadjacent to the one tile.
 21. The tiled display structure of claim 20,wherein the back-side electrodes of the one of the tiles areelectrically connected to the back-side electrodes the adjacent tilewith one or more of: (i) a jumper comprising a jumper substrate,connection posts, and a fractured or separated tether; (ii) one or morewire bonds; and (iii) one or more wrapped connections.
 22. The tileddisplay structure of claim 20, wherein at least some of the back-sideelectrodes of a subset of the array of tiles are commonly connected andeach of the commonly connected back-side electrodes is electricallyconnected to a bus connection.
 23. The tiled display structure of claim20, wherein the tiles are disposed in rows and wherein the back-sideelectrodes of ones of the tiles in a row are electrically connected incommon.
 24. The tiled display structure of claim 1, wherein the tilesubstrate is flexible.
 25. The tiled display structure of claim 24,wherein, for at least one of the tiles, a portion of the tile substrateof the tile is at least partially folded behind a portion of the tilesubstrate of another one of the tiles that is adjacent to the tile. 26.The tiled display structure of claim 25, wherein the portion of the tilesubstrate is a bezel portion or a pigtail portion.
 27. The tiled displaystructure of claim 1, wherein the tile substrate comprises a pigtailthat electrically connects the one or more light emitters to a busconnection.
 28. The tiled display structure of claim 1, wherein the tileis a removable or replaceable tile. 29-36. (canceled)